1. Field of the Invention
The present invention relates to an image processing apparatus, an image processing method and an image pickup apparatus, and in particular, to a technique for performing a dynamic range compression.
2. Description of the Related Art
Japanese Patent No. 2748678 discloses a gradation correction device including a luminance signal conversion device which forms a luminance signal from R, G and B signals, a correction coefficient calculation device which calculates a ratio of the result that the luminance signal is gamma-converted to a gradation characteristic of any shaped desired to the luminance signal and a multiplying device which multiplies the output of the correction coefficient calculation device by the R, G and B input signals.